Methods and Apparatuses for Compensating for Retinitis Pigmentosa

ABSTRACT

A system and methods for compensating for retinitis pigmentosa for a user include using a head-mounted and user-controllable device that can minify the image to more closely match the user&#39;s reduced field of view. The user may adjust the amount of minification and may also adjust the magnification of the image.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 16/503,098, entitled “Methods and Apparatuses forCompensating for Retinitis Pigmentosa” and filed on Jul. 3, 2019, whichclaims the benefit of U.S. Provisional Application No. 62/694,173,entitled “Compensating for Retinitis Pigmentosa: Using dynamic shifts infield of view and magnification” and filed Jul. 5, 2018, the contents ofboth of which are hereby incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention generally relates to a vision-enhancement systemand methods, and, more particularly, to a head-mounted anduser-controllable method and system for vision-enhancement and a systemand method for configuring a vision-enhancement system to compensate forthose suffering from retinitis pigmentosa.

Discussion of the Background

The normal human visual system establishes a non-magnifiedrepresentation of a scene in the visual periphery with a high-resolutionrepresentation at the center of the visual field. Thus, the cornea andlens of the eye focuses a viewed scene onto the retina, which includesthe fovea near the center of vision, and a peripheral area. The fovea isa small area composed of closely packed cones near the center of theMacula lutea of the retina. The fovea is responsible for sharp centralvision which is necessary for activities where visual detail is ofprimary importance, such as reading and driving.

The fovea is greatly expanded at the visual cortex and represents asignificant magnification mechanism that allows a normally sightedperson to discern the region of the visual world that is in “focus” on(faces, titles of dish soap, text), but sees that region in the broadcontext of an overall visual field.

People with retinitis pigmentosa (referred to herein as “RP”) sufferfrom “tunnel vision” with an accompanying reduction in the ability tocapture enough light in low light situations (i.e., dusk, nighttime,theaters, and the like) to be able to navigate safely. These peopleretain central vision but lose most peripheral vision. In normaldaylight situations, the effect of RP is to easily swamp the visionduring normal sunlight to the point that the visual scene is obscured.The visual field can be as narrow as 1 degree (the width of your thumbat arm's length). Such people have difficulty with mobile activitiessuch as navigating and recognizing both people and objects at a distanceand can have difficulty reading. These disabilities greatly diminishtheir quality of life, greatly limiting their ability to socialize,shop, cook and travel.

Traditionally, the effects or RP may be compensated using an optical ordigital “reverse telescope.” This solution, however, is inadequatebecause the magnification, field and focus point is fixed. The person isrestricted to using the same parameters for all situations. This limitsthe utility of the device and its value to those suffering from RP.

Thus, there is a need in the art for a method and apparatus that permitsfor enhanced representation of the visual world that also enablesmobility for navigation and recognition. The methods and apparatusshould be easy to use, allow the user to control what is being viewed,and be inexpensive.

BRIEF SUMMARY OF THE INVENTION

The present invention overcomes the limitations and disadvantages ofprior art vision-enhancement systems and methods by providing the userwith a head-mounted, user-adjustable field of view system that providesenhancements for various low vision problems.

It is one aspect to provide a device that can present to the user, inreal-time, an enhanced video image of a scene surrounding the user sothat the user can perform routine tasks. Certain embodiments include: 1)a head-mounted video camera that can obtain an input stream of videoimages of the scene in front of the user's head; 2) a processor toprocess the stream of input video images into a stream of output imagesthat corrects for the user's vision deficiencies; and 3) a display forthe processed video images that is viewable by the user. In certainembodiments, the system presents an image of adjustable size andpresents a scene within a smaller field of view than what would beviewed with normal vision.

It is another aspect to provide a wearable and portablevision-enhancement system for persons suffering from RP. The systemincludes a memory including a stored program; a camera mounted on theuser aimed to view the scene in front of the user's head and operable toobtain input video images of the scene; a processor programmed toexecute the stored program to transform the input video images into astream of output video images. In one embodiment, the transformationfrom input video images results in output video images that occupy asmaller field of view than uncorrected vision. In effect, the systemprovides a zoomed-out version of the input images similar to lookingthrough the “wrong” end of a telescope. The zoomed-out images arereferred to herein as being “minified,” which is the opposite of beingmagnified. This minified view gives the patient a smaller field of viewthat can be “scanned” with the patient's limited (often 1 degree) visualfield. The program is also operable in response to a command by thepatient after viewing the minified contextual scene to magnify withinthe smaller FOV so as to focus in on a particular feature of the scene(another person's face, a label on a package, title of a book, etc.).

It is one aspect to provide a portable vision-enhancement systemwearable by a user. The system includes: a memory including a storedprogram; a camera mounted on the user aimed to view the scene in frontof the user and operable to obtain input video images of the scene; aprocessor programmed to execute the stored program to change the inputvideo images into a stream of output video images; a screen disposed todisplay the output video images for viewing by the user; and auser-operable controller for generating an input to the processor bywhich the size of the output video images are adjusted.

It is another aspect to provide a method for compensating for retinitispigmentosa for a user using a system including a camera, a processor,and a screen. The method includes: accepting a stream of video imagesfrom the camera; processing the accepted stream of video images in theprocessor into a stream of output video images; and accepting an inputfrom the user to adjust the size of the output video images on thescreen.

These features, together with the various ancillary provisions andfeatures which will become apparent to those skilled in the art from thefollowing detailed description, are attained by the vision-enhancementsystem and method of the present invention, preferred embodimentsthereof being shown with reference to the accompanying drawings, by wayof example only, wherein:

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIGS. 1A, 1B, and 1C show a first embodiment user-controllablevision-enhancement system, where FIG. 1A shows the system on a user,FIG. 1B shows a smartphone used in the system and FIG. 1C shows the bodyof the goggle used in the system;

FIG. 1D shows a system which may be used to configure avision-enhancement system;

FIG. 2 shows an output image of a scene as would be presented to a userprior to being minified;

FIG. 3 shows a minified output image of the scene FIG. 2 ; and

FIG. 4 shows a magnified minified output image of the scene of FIG. 3 .

Reference symbols are used in the figures to indicate certaincomponents, aspects or features shown therein, with reference symbolscommon to more than one figure indicating like components, aspects orfeatures shown therein.

DETAILED DESCRIPTION OF THE INVENTION

Certain embodiments of the inventive vision-enhancement system describedherein include: 1) a video camera to capture the scene that would be inthe user's field of view if the user was not wearing the system; 2) aprocessor to image process the video of the captured scene; and 3) ascreen to present the processed video images to the user's eyes. Themodified video image compensates for the user's particular visionproblem, such as tunnel vision, by providing more of the central imageof interest to the more active, less impacted portions of the user'seyes, while retaining the peripheral context of the scene. Thus, theimage of the of the scene is presented to the user according to an imagetransformation that maps the captured image, pixel-by-pixel, to an imagethat presents a smaller field of view than if it were viewed without thesystem and is thus more useful to the user.

In one embodiment, minified images are presented to the user of thevision-enhancement system. The term “minified” is used to denote anoutput image that is a zoomed out version of the input images. Thus, forexample, a scene that would be viewed without enhancement over a70-degree field of view is reduced in size so that the same scene isviewed within a smaller field of view, such as, for example and withoutlimitation, a 35 degrees. A minified image is similar to the effect oflooking through the “wrong” end of a telescope and is the opposite ofbeing magnified. This minified view gives the patient suffering from RPa contextual view of the scene. The image-processed video modifies ascene in a way that allows the user to more easily recognize people oridentify items in their surroundings. Thus, the user may be able toidentify items on the supermarket shelf, recognize friends andneighbors, read street signs, and sit in an armchair to read a book. Inother embodiments, the user is also able to magnify or zoom in to theimage to allow greater detail to be discerned.

By way of a specific embodiment, FIGS. 1A, 1B, and 1C show a firstembodiment user-controllable vision-enhancement system 100, where FIG.1A shows the system on a user, FIG. 1B shows a smartphone used in thesystem and FIG. 1C shows the body of the goggle used in the system.System 100 includes a smartphone 110 supported in headset 120.Smartphone 110 includes the electronics necessary for thevision-enhancement system 100, including a processor and memory (notshown), a forward-facing camera 111, as shown in FIG. 1A, and a screen113 on the side opposite the camera, as shown in FIG. 1B. Smartphone 110also includes an electrical connector 117 and may also include abackward-facing camera 115, which may be used in certain embodiments. Asdescribed subsequently, processed camera images are displayed on oneportion of screen 113 shown as a left area 112 and a second portion ofthe screen shown as a right area 114.

Headset 120 include a body 122 and a strap 125 for holding the headseton the user's head and a connector 128 that mates with smartphoneconnector 117. Body 122 includes, as shown in FIG. 1A, a pair of clamps121 for removably restraining smartphone 110 and making the electricalconnection between connectors 117 and 128, and input device 123 forproviding input to the smartphone through the connectors and, as shownin FIG. 1C, a left lens 124 and right lens 126 and a focusing wheel 127.When assembled as in FIG. 1A, with smartphone 110 held in place byclamps 121, system 100 presents what is displayed in area 112 of screen113, through lens 124, to the user's left eye, and what is displayed inarea 114 of the screen, through lens 126, to the user's right eye. Theuser may use focusing wheel 127 to adjust the focus. In certainembodiments, headset 120 are adapted to accept user input from inputdevice 123, which may control or otherwise provide inputs to theaccepted smartphone 110.

In certain embodiments, smartphone 110 is provided with programming, asthrough a vision-enhancement application (referred to herein as a “VEApp”) which can: 1) operate camera 111 in a video mode to capture astream of “input images”; 2) perform image processing on each inputimage to generate a stream of “output images”; and 3) present the streamof output images to screen 113. In certain embodiments, each of thestream of output images is presented sequentially side-by-side as twoidentical images—one in area 112 and one in area 114. Further, it ispreferred that vision-enhancement system 100 operate so that the timedelay between when the input images are obtained and when the outputimages are provided to screen 113 be as short as possible so that a usermay safely walk and interact with the environment with headset 120covering their eyes.

In certain embodiments, the VE App may also provide a menu of optionsthat allow for the modification of how vision-enhancement system 100generates an output image from an input image. Thus, for example,vision-enhancement system 100 may execute image-processing algorithmshaving parameters, where the parameters are changeable through the menuby, for example, setting parameter values for magnification, or the sizeand shape of magnification of the output image.

Vision-enhancement system 100 has adjustable features that allow it tomatch the physiology of the user for use in different settings. Thesefeatures are generally set once for each user, possibly with the needfor periodic adjustment. Thus, for example, given the spacing betweenscreen 113 and the eyes of user U, focusing wheel 127 permits for anoptimal setting of the distance to lenses 124 and 126. In addition,lenses 124 and/or 126 may include refractive error correction. Further,it is important that the viewed spacing between the images in areas 112and 114 match the user's interpupillary distance (IPD). This may beaccounted for, by example, by shifting the spacing of the output imagesin areas 112 and 114 to match the IPD.

In various embodiments, the user may adjust settings using input device123, which may be a touchpad, and which is electrically connected tosmartphone 110, which is further programmed to modify the VE Appaccording to such inputs; a Bluetooth game controller that communicateswith the smartphone 110 via Bluetooth; voice control using themicrophone of the phone; or gesture control using available devices suchas the NOD gesture control ring (see, for example,http://techcrunch.com/2014/04/29/nod-Bluetooth-gesture-control-ring/).

In addition, there are other features of vision-enhancement system 100that can either be set up once for a user or may be user-adjustable.These features may include, but are not limited to, adjustments to themagnitude, shape, size, or placement of minified or magnified portionsof the output image, and color enhancement functions such as contrast,blur, ambient light level or edge enhancement of the entire image orportions of the image. In other embodiments, the compass and/oraccelerometers within smartphone 110 may be used for enhancingorientation, location, or positioning of output images.

In certain embodiments, sound and/or vibration may be provided onsmartphone 110 to generate for proximity and hazard cues. In otherembodiments, the microphone of smartphone 110 can be used to enter voicecommands to modify the VE App. In certain other embodiments, imagestabilization features or programming of smartphone 110 are used togenerate output images.

In one embodiment, by way of example only, headset 120 are commerciallyavailable virtual-reality headset, such as Samsung Gear VR (SamsungElectronics Co. Ltd., Ridgefield Park, N.J.) and smartphone 110 is aGalaxy Note 4 (Samsung Electronics Co. Ltd., Ridgefield Park, N.J.). TheSamsung Gear VR includes a micro USB to provide an electrical connectionto the Galaxy Note 4 and has as input devices 123 a touch pad andbuttons.

It will be understood by those in the field that vision-enhancementsystem 100 may, instead of including a combination of smartphone andheadset, be formed from a single device which includes one or morecameras, a processor, display device, and lenses that provide an imageto each eye of the user. In an alternative embodiment, some of thecomponents are head-mounted and the other components are incommunication with the head-mounted components using wired or wirelesscommunication. Thus, for example, the screen and, optionally the camera,may be head-mounted, while the processor communicates with the screenand camera using wired or wireless communication.

Further, it will be understood that other combinations of elements mayform the vision-enhancement system 100. Thus, an electronic device whichis not a smartphone, but which has a processor, memory, camera, anddisplay may be mounted in headset 120. Alternatively, some of theelectronic features described as being included in smartphone 110 may beincluded in headset 120, such as the display or communicationscapabilities. Further, the input control provided by input device 123may be provided by a remote-control unit that is in communication withsmartphone 110.

FIG. 1D illustrates, without limitation, one embodiment of a clinicalsetup 140 that a clinician may user to configure vision-enhancementsystem 100. Clinical setup 140 may allow a clinician to determine andsetup the VE App by setting an IPD, the field of view (fov), backgrounddimming, ambient light level, as well as parameters that are alsouser-adjustable, such as the size, shape, magnification, and location ofenhanced vision features.

Clinical setup 140 thus allows for the adjustment or parameters withinor used by the VE App that smartphone 110 runs to implement thevision-enhancement system 100. Clinical setup 140 includes a monitor142, a Wi-Fi device 144 to allow screen 113 of smartphone 110 to bedisplayed on the monitor, and a Bluetooth controller 146 to communicatevia Bluetooth with smartphone 110. In general, clinical setup 140accepts a video output from smartphone 110 of display 113 and projectswhat the user would see when using vision-enhancement system 110 onmonitor 142.

In certain embodiments, features or aspects of the inventivevision-enhancement system 100 may be adjusted by a clinician usingclinical setup 140. Using the setting up vision-enhancement system 100,screen 113 of smartphone 110 is mirrored on a monitor using Wi-Fi device144, for example, so that the clinician can view what the user isviewing in vision-enhancement system 100. The VE App on smartphone 110includes a menu that allows for the selection of certain parameters thatoperate vision-enhancement system 100.

The clinician has access to the commands in the menu of the VE App viaremote Bluetooth controller 146. In this way, the clinician can “tune”the device to the specific visual demands of the user.

In certain embodiments, Wi-Fi device 144 can be used to remotely add,augment or modify functions to allow vision-enhancements, mirror thedisplay, monitor and control VE App configurations in a clinicalenvironment. In certain embodiments, Bluetooth controller 146 can beused to control or modify visual enhancement functions. In certain otherembodiments, the VE App may be reconfigured in a purely magnifiedformat, making it possible for the low vision user to place phone calls,utilize maps, read announcements and perform all visual functionscurrently available to those with normal vision.

Examples of functional control of vision-enhancement system 100 providedby clinical setup 140 through the operation of the VE App may includebut are not limited to: 1) mirroring the user's display via Wi-Fi; and2) controlling the minification and/or magnification of the outputimage. The clinician will have the facility to control the low visionparameters such as amount and placement of minification ormagnification, contrast, edge enhancement ambient level and other visualenhancements to customize the device for the user.

To better appreciate how the apparatus and methods described hereinalter images for viewing, FIG. 2 presents an example of what avision-enhancement system 100 displays without the VE App running—thatis, what would be normally shown on the screen prior to minifying theimage.

FIG. 2 illustrates an image 200 in area 112 which may be presented toone or both of display areas 112/114 prior to the alteration of theimage as described herein. In general, image 200 is representative ofany image or portion of an image captured by camera 111 and stored inthe memory of smartphone 110. Image 200 includes an output image Sofascene as the image of the scene prior to minification. Typically, anoutput image S occupies approximately 70 degrees when viewed by theuser. That is, when area 112 is placed for viewing, the image presentedsubtends 70 degrees of the user's field of view.

For reference, FIG. 2 shows two portions of area 112 that are discussedin greater detail with reference to FIGS. 3 and 4 . These portionsare: 1) the outline of an output area 203 of area 112 into which theimage S will modified for presentation; and 2) a circle representing auser's visual field 203 on area 112. The size of output area 203 isselectable by the user, the size of visual field 201 depends on thevision of the user, and the location of the visual field on area 112depends on the gaze of the user—that is, it follows the movement oftheir eyes relative to the area.

FIG. 3 illustrates a minified output image of the scene FIG. 2 . In anillustrative example, VE App of the vision-enhancement system 100 isoperated to place output images within output area 203 and is alsoprogrammed to accept input through input device 123, as discussed above,to control the size of output area 203 of display areas 112/114.

Thus, for example, one embodiment of system 100 performs atransformation or mapping of the output image S into output image 300,as shown in FIG. 3 and which may be, for example, one or both of displayareas 112/114. In image 300, the user has manipulated input device 123to select the size of output area 203. The unaltered output image, suchas scene S, is reduced in size to fit within output area 203 and thuspresent a minified output image S′, which is, in effect, output image Sreduced in size and bounded by the output area 203. Due to the reducedarea, an area B between output area 203 and area 112 does not containthe scene and may, for example, be colored black.

It will be appreciated that since display areas 112/114 are located atsome specific distance from the user's eyes, output area 203 will thusoccupy a visual field in proportion to the size of the output area. Inone embodiment, output area 203 is smaller than area 112 and occupies afield of view that is less than or equal to 45 degrees, or,alternatively, to a field of view that is less than or equal to 35degrees field. Thus, for example, output area 203 may occupy between 15and 30 degrees when viewed by the user or may occupy 15 degrees, 20degrees, 25 degrees, or 30 degrees.

FIG. 3 also shows, for reference, the user's visual field 201. Theactual location of visual field 201 depends on where the user islooking. Thus, visual field 201 will move about output area 203 as theuser directs their gaze to different portions of output area 203. As isapparent from comparing FIGS. 2 and 3 , when output image S is minifiedas output image S′, the angular size of the image is decreased and moreof the original output image S falls within image user's visual field201.

It will also be appreciated that output area 203 may be rectangular, asin the above embodiments, or may have a circular shape, or may be placedanywhere within image 300 as is appropriately tailored to a specificuser's vision needs.

In addition to minifying the image, alternative embodiments includevision-enhancement system 100 programmed to enhance the light availablein low light situations and reduce the intensity of light in brightlight situations in response to the user's command.

FIG. 4 shows a magnified minified output image of the scene of FIG. 3 .In an illustrative example, VE App of the vision-enhancement system 100is programmed to accept input through input device 123, as discussedabove, to control the scale of output area 203 of display areas 112/114.

Thus, for example, FIG. 4 , shows an image 400 which includes an outputimage S″ within output area 203, where the output area is determined asdescribed above with reference to FIG. 3 . Output image S″ is amagnified view of minified image S′—that is, S″ is a magnified minifiedimage. In certain embodiments, the magnification of the minified imageis modified by the user through input device 123, as discussed above. Inother words, the user may adjust the magnification of the minifiedimage.

As is apparent from comparing FIGS. 3 and 4 , magnifying a minifiedimage permits the user wearing system 100 to see greater detail, which,in turn, facilitates reading and other activities.

In one embodiment, a VE App is provided to smartphone 110 which performsimage processing on each image of the stream of video images and thenpresents each processed area simultaneously to areas 112 and 114. VE Appmay perform the following steps:

1) start the method, which runs continuously until stopped by the user.

2) capture images the scene. Images from stream of images are read fromcamera into memory. Depending on the architecture of the particulardevice and the capabilities and performance of the camera and theprocessing CPU, this may be done in one of two ways: a) read the entireimage into memory and then process all pixels in the image, or b) read acollection of pixels (essentially a slice of the image) and process itwhile another slide is being read.

3) determine the size of the image output area 203. This may be presetin the VE App or may be controllable through input device 123.

4) minify the captured image to fit within output area 203 andoptionally blacken the area between output area 203 and the edge ofareas 112/114.

5) accept input from input device 123 to magnify the minified image.

Among the attributes of this embodiment are:

-   -   1. Dynamic control by the user of minification size of the field        of view.    -   2. Dynamic control by the user of magnification within the field        of view.    -   3. User control of these parameters that provides the patient        with the power to control the incoming scene. These parameters        will change depending upon what is being viewed, ranging from        faces, to text, to theater events. The auto-focus camera assures        that image will be in focus at all distances.    -   4. Use of the camera/display system to compensate for low light        conditions, making the images bright enough for an RP patient to        see in twilight.    -   5. Enclosure of the entire scene in a headset, eliminating        excessive light and glare that are particularly troubling for        the RP patient.

Each of the embodiments of the devices and methods described herein isin the form of a computer program that executes as an app on asmartphone. It will be appreciated by those skilled in the art,embodiments of the present invention may be embodied in a specialpurpose apparatus, such as a headset which contain the camera,processor, and screen, or some combination of elements that are incommunication and which, together, operate as the embodiments described.

It will be understood that the steps of methods discussed are performedin one embodiment by an appropriate processor (or processors) of aprocessing (i.e., computer) system, electronic device, or smartphone,executing instructions (code segments) stored in storage. It will alsobe understood that the invention is not limited to any particularimplementation or programming technique and that the invention may beimplemented using any appropriate techniques for implementing thefunctionality described herein. The invention is not limited to anyparticular programming language or operating system.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure or characteristicdescribed in connection with the embodiment is included in at least oneembodiment of the present invention. Thus, appearances of the phrases“in one embodiment” or “in an embodiment” in various places throughoutthis specification are not necessarily all referring to the sameembodiment. Furthermore, the particular features, structures orcharacteristics may be combined in any suitable manner as would beapparent to one of ordinary skill in the art from this disclosure in oneor more embodiments.

Similarly, it should be appreciated that in the above description ofexemplary embodiments of the invention, various features of theinvention are sometimes grouped together in a single embodiment, figure,or description thereof for the purpose of streamlining the disclosureand aiding in the understanding of one or more of the various inventiveaspects. This method of disclosure, however, is not to be interpreted asreflecting an intention that the claimed invention requires morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive aspects lie in less than allfeatures of a single foregoing disclosed embodiment. Thus, the claimsfollowing the Detailed Description are hereby expressly incorporatedinto this Detailed Description, with each claim standing on its own as aseparate embodiment of this invention.

Thus, while there has been described what is believed to be thepreferred embodiments of the invention, those skilled in the art willrecognize that other and further modifications may be made theretowithout departing from the spirit of the invention and it is intended toclaim all such changes and modifications as fall within the scope of theinvention. For example, any formulas given above are merelyrepresentative of procedures that may be used. Functionality may beadded or deleted from the block diagrams and operations may beinterchanged among functional blocks. Steps may be added or deleted tomethods described within the scope of the present invention.

What is claimed is:
 1. A portable vision-enhancement system wearable bya user, said system comprising: a memory including a stored program; acamera mounted on said user aimed to view the scene in front of the userand operable to obtain input video images of said scene; a processorprogrammed to execute the stored program to change said input videoimages into a stream of output video images; a screen disposed todisplay said output video images for viewing by the user; and auser-operable controller for generating an input to said processor bywhich the size of the output video images is adjusted, such that, whensaid stored program is executed by said processor and the user operatessaid user-operable controller, a size of said output video images ofsaid scene on said screen is adjusted.
 2. The portablevision-enhancement system of claim 1, where the size of said outputvideo images occupies less than a 35 degree field of view of the user.3. The portable vision-enhancement system of claim 2, where said lessthan a 35 degree field of view of the user is between 15 and 30 degrees.4. The portable vision-enhancement system of claim 2, where said lessthan a 35 degree field of view of the user is 15 degrees, is 20 degrees,is 25 degrees, or is 30 degrees.
 5. The portable vision-enhancementsystem of claim 1, further comprising: a user-operable controller forgenerating an input to said processor by which the magnification of theoutput video images is adjusted, such that, when said stored program isexecuted by said processor and the user operates said controller, theuser adjusts the magnification said output video images within theadjusted size of said output video images.
 6. The portablevision-enhancement system of claim 1, further comprising: auser-operable controller for generating an input to said processor bywhich the maximum light intensity of the output video images isadjusted, such that, when said stored program is executed by saidprocessor and the user operates said controller, the user adjusts theintensity of light of said output video images on said screen.
 7. Theportable vision-enhancement system of claim 1, further comprising aheadset and an electronic device attached to said headset, where saidcamera, said processor, and said screen are components of saidelectronic device.
 8. The portable vision-enhancement system of claim 7,where said electronic device is removably attached to said headset. 9.The portable vision-enhancement system of claim 7, where said electronicdevice is a smartphone.
 10. A method for compensating for retinitispigmentosa for a user using a system including a camera, a processor,and a screen, said method comprising: accepting a stream of video imagesfrom the camera; processing the accepted stream of video images in theprocessor into a stream of output video images; accepting an input fromthe user; and adjusting the size of the output video images on thescreen according to the accepted input.
 11. The method of claim 10,where the adjusting adjusts the size of the output video images of sceneon the screen to occupy less than a 35 degree of the field of view ofthe user.
 12. The method of claim 11, where the less than a 35 degree ofthe field of view of the user is between 15 and 30 degrees.
 13. Themethod of claim 11, where the less than a 35 degree of the field of viewof the user is 15 degrees, is 20 degrees, is 25 degrees, or is 30degrees.
 14. The method of claim 10, further comprising: accepting aninput from the user to adjust the magnification of the output videoimages on the screen.
 15. The method of claim 10, further comprising:accepting an input from the user to adjust the intensity of light of theoutput video images on the screen.
 16. The method of claim 10, wheresaid camera, processor, and screen are contained in a smartphone.